Apple aims to patent fall-detecting iPod

The company has applied for a patent on technology that would allow a portable media player to detect when it is falling and then stop reading or writing to the hard drive. Such technology would work by detecting the acceleration that accompanies a drop.

"The portable-computing device protects its disk drive by monitoring for such accelerations and operating to avoid usage of the disk drive during periods of acceleration," Apple said in the patent application, which was published Dec. 16. "Through such protection, the likelihood of damage to the disk drive or loss of data stored on the disk drive is able to be substantially reduced."

IBM began including a similar feature on its ThinkPad notebook line in October 2003. Apple's patent application was filed in June 2003, but it wasn't published until last week.

Others are trying different approaches. Hitachi is working to make the hard drive's read/write arm smaller and more nimble. That would make the drive less likely to be damaged in a fall.

Start-up drive maker Cornice has discussed plans for a 3GB, 1-inch drive whose read/write arm physically locks when the drive isn't in use. That won't necessarily protect a drive that is in the process of reading or writing when the device is dropped.

However, the approach taken by IBM and Apple has its limits. It takes time for a device to notice the acceleration. Thus, the product has to be dropped from a certain height for the feature to kick in.

Apple also applied for several other patents that have been published in recent weeks. One covers the technology that musicians and record labels use to submit music to the iTunes Music Store. Several others cover video-conferencing technology. Another patent, published Wednesday, appears to cover the concept included in Mac OS X Panther's Expose feature, where overlapping windows are separated on the same screen.

An Apple representative declined to comment.